Sesame Street characters greet first lady Michelle Obama (r.) and Jill Biden, wife of Vice President Joe Biden, during a USO and Sesame Street event honoring National Guard members and their families on April 14, in Columbus, Ohio. Mrs. Obama will appear on 'iCarly' in January to promote 'Joining Forces,' an organization supporting military families.

The point of Mrs. Obama’s guest spot is to promote Joining Forces, an organization aimed at supporting members of the military and their families. The first lady’s a big booster of this group.

Why did the White House choose a show about a webcast produced by a teen named Carly and her best friends Sam (a girl, wacky) and Freddie (a boy, techie) as a forum here? Because in “iCarly,” Carly’s dad is a military officer who is always off somewhere else doing something important and never appears. Carly lives with her older brother Spencer in a great loft that is supposedly in Seattle, with no parents. No, we don’t know anything about the mother – they never talk about it.

Obama will turn up in an episode in which Sam and Freddie break rules and set up a webchat between Carly and her dad on his birthday. (Having seen this show before, we bet the “rule breaking” involves something like hacking into the US nuclear control network during study hall.) The first lady discovers this. Hilarity ensues, followed by learning and a hug.

That sounds great. But what we really want to know is this: will Michelle Obama get to eat spaghetti tacos?

That’s iCarly’s signature dish. Spencer made them one night for dinner and the gang had to eat them. They loved them – now Carly (the character, played by actress Miranda Cosgrove) insists they are one of her favorite dishes.

The scary thing is that the show’s spaghetti tacos sparked a real spaghetti tacos trend – just Google the phrase and stand back. Dozens of real-life recipes will appear on your screen. Apparently they are a popular item at kid birthday parties, and on the dinner table of adults who are too self-consciously hip for their own good.

The official recipe can be found here. Trust us, it’s not very involved.

It’s true that spaghetti tacos are messy. Obama does not look like a messy person, so perhaps she’ll politely decline, if they’re offered.

Anyway, the episode in question will appear in January. It was written especially for the first lady and her Joining Forces initiative, after she asked about appearing on the show, according to Nickelodeon’s chief.

Does the network worry that perhaps they’ll be giving the Obama administration some free advertising right when the 2012 campaign starts to heat up?

“It’s a feel-good initiative,” said Ms. Zarghami, “and regardless of your political affinity, everybody cares about these families, so it just feels right.”